Expose yourself to as many useful languages as you can. Learn a bit about the (business-wise) useless ones too -- they can still teach you a thing or two. The really important thing to learn in school is the theory of developing systems that work, and doing so as simply and elegantly as possible. Any company worth working for will pick up on that. If you really learned from your CS degree, learning a new language will simply be a study in syntax. For a true nerd, it is easy enough to "master" the nuances of a specific language in your free time; learn as much of the hard stuff in school while you can!